1 files changed, 58 insertions, 0 deletions
diff --git a/library/stdarch/crates/core_arch/src/wasm32/memory.rs b/library/stdarch/crates/core_arch/src/wasm32/memory.rs
new file mode 100644
index 000000000..b5cf13e98
--- /dev/null
+++ b/library/stdarch/crates/core_arch/src/wasm32/memory.rs
@@ -0,0 +1,58 @@
+#[cfg(test)]
+use stdarch_test::assert_instr;
+
+extern "C" {
+    #[link_name = "llvm.wasm.memory.grow"]
+    fn llvm_memory_grow(mem: u32, pages: usize) -> usize;
+    #[link_name = "llvm.wasm.memory.size"]
+    fn llvm_memory_size(mem: u32) -> usize;
+}
+
+/// Corresponding intrinsic to wasm's [`memory.size` instruction][instr]
+///
+/// This function, when called, will return the current memory size in units of
+/// pages. The current WebAssembly page size is 65536 bytes (64 KB).
+///
+/// The argument `MEM` is the numerical index of which memory to return the
+/// size of. Note that currently the WebAssembly specification only supports one
+/// memory, so it is required that zero is passed in. The argument is present to
+/// be forward-compatible with future WebAssembly revisions. If a nonzero
+/// argument is passed to this function it will currently unconditionally abort.
+///
+/// [instr]: http://webassembly.github.io/spec/core/exec/instructions.html#exec-memory-size
+#[inline]
+#[cfg_attr(test, assert_instr("memory.size", MEM = 0))]
+#[rustc_legacy_const_generics(0)]
+#[stable(feature = "simd_wasm32", since = "1.33.0")]
+#[doc(alias("memory.size"))]
+pub fn memory_size<const MEM: u32>() -> usize {
+    static_assert!(MEM: u32 where MEM == 0);
+    unsafe { llvm_memory_size(MEM) }
+}
+
+/// Corresponding intrinsic to wasm's [`memory.grow` instruction][instr]
+///
+/// This function, when called, will attempt to grow the default linear memory
+/// by the specified `delta` of pages. The current WebAssembly page size is
+/// 65536 bytes (64 KB). If memory is successfully grown then the previous size
+/// of memory, in pages, is returned. If memory cannot be grown then
+/// `usize::MAX` is returned.
+///
+/// The argument `MEM` is the numerical index of which memory to return the
+/// size of. Note that currently the WebAssembly specification only supports one
+/// memory, so it is required that zero is passed in. The argument is present to
+/// be forward-compatible with future WebAssembly revisions. If a nonzero
+/// argument is passed to this function it will currently unconditionally abort.
+///
+/// [instr]: http://webassembly.github.io/spec/core/exec/instructions.html#exec-memory-grow
+#[inline]
+#[cfg_attr(test, assert_instr("memory.grow", MEM = 0))]
+#[rustc_legacy_const_generics(0)]
+#[stable(feature = "simd_wasm32", since = "1.33.0")]
+#[doc(alias("memory.grow"))]
+pub fn memory_grow<const MEM: u32>(delta: usize) -> usize {
+    unsafe {
+        static_assert!(MEM: u32 where MEM == 0);
+        llvm_memory_grow(MEM, delta)
+    }
+}